Casting coke knock-out and cleaning



July 16, 1963 A. H. FREEMAN ETAL.

CASTING CORE KNOCK-OUT AND CLEANING MACHINE AND METHOD Filed May 11, 1 962 PDEE H. FREEMAN BY' FREDERICK J. P/CHARD ATTORNEYS United States Patent O 3,097,452 CASTENG CURE KNCK-OUT AND CLEANlNG MACHNE AND METHUD Ardea H. Freeman, Granger, and Frederick I. Pichard,

South Bend, ind., assignors to Beil Intercontinental Corporation, South Bend, Ind.

Filed May 11, 1962, Ser. No. 194,116 Claims. (Cl. 51-13) This invention relates to machines `and methods for sequentially processing rough castings or the like through rough-cleaning and finish-cleaning operations, by means of a single, low cost machine. Such machines may be effectively employed for example to perform, in sequence, core knockout and rough cleaning and finish clean-up processes, on castings of widely diiferent shapes and sizes. More speciiically, the present invention relates to further improvements in the art which is dealt with by our prior application Serial No. 85,045.

The present invention provides in a single blast machine system, improved means for selectively passing the refuse and blast media mixture through alternative cycling systems for more eflicient use of the blast media reconditioning components during successive stages of the Workpiece treating process; whereby the system is adapted for more ecient overall processing of the workpieces incidental to only one loading thereof, and without requiring any intermediate handling of the workpieces. Hence, the time loss and labor and capital expenses heretofore necessarily incidental to -use of multiple machines for such purposes are eliminated. Other objects and advantages of the machine system of the invention will be apparent from the specication hereinafter, having reference to the accompanying drawing wherein:

FIG. l is a somewhat schematic elevational view, with portions broken away to show interior details, of one form of machine system of the invention.

As shown in the drawing, a machine system of the invention may be constructed generally to comprise a workpiece support and carrying device such as -a tumble blast unit including a cradle type conveyor 12 which supponts yand tumbles the lo-ad of castings or other workpieces which are to be processed, as indicated at 15. A blast machine as indicated at 16 is disposed -above the load of castings and operates to sling shot or other blast media against the workpieces at certain stages of the process as will be more fully explained hereinafter. The hopper and feed chute for supplying blast media to the unit 16 is indicated at 1S, and the conveyor for carrying away spent med-ia and debris is indicated at 20".

With ya view to simplification of this specification the workpiece support and centrifugal blast machine components referred to will not be illustrated and described in further detail; the construction and operation of typical examples thereof being fully disclosed and explained respectively in U.S. Patents 2,104,055 -and 2,819,562. However, it is to be understood that in lieu of the specific form of workpiece supporting and tumbling and shot throwing devices illustrated herein `and disclosed in the referenced patents, any other suitable form of equipment for this purpose may be employed; such as for example a swing table machine as disclosed in U.S. Patent No. 3,041,786.

In any case in accord with the present invention the blast machine 10 is coupled into a blast media and debris circulating and separation system which may include an elevator 22 as shown at FIG. 1 discharging the debris and labrasive mixture from the machine lil through a cross conveyor 24 to a screen and hopper and separator combination designated 25, 26 and 2S, respectively. The construction and operation of a separator of the pre- 3,097,452 Patented `Fully 16, 1963 ICC ferred form for this purpose is illustrated and described in full detail 4for example in U.S. Patent No. 3,005,547. As shown herein, the separator includes a scalping screen 29 which conveys coarse debris to a waste chute 30, and a sand or tine refuse discharge spout 31 delivering also into any suitable take-away device; and a reconditioned blast media discharge chute delivering into the blast machine feed hopper P18. The hopper 26 delivers through a valve 33 to a surge tank or bin 34 which in turn delivers through a valve '3S to the conveyor 20. The hopper 18 includes a by-pass control valve 36 delivering feed material through a conduit to the blast machine 16. Operation of the system will now be explained.

The Rough Cleaning Cycle When castings or the like are to be processed they are rst stripped from their molds and loaded by any suitable means into the blast cabinet l() of the machine; the valve 33 being open. The door of the cabinet is then closed and if the castings contain appreciable quantities of loose sand or other core or mold materials, the castings may first be tumbled and/ or turned for a predetermined time to cause the more easily displaced sand and/or core materials to fall out of the castings. During this phase of the process the blast unit 16 remains idle. Hence, the sand and debris falling from the workpieces into the conveyor Ztl is passed to the surge tank 34. In some cases this preblast tumbling operation will not be employed, but in any case fthe `blast unit 16 will now be activated and the valve 35 is opened, whereby a predetermined charge of blast media is introduced through the hopper 18 and feeds to the blast machine 16 while the workpiece support continues to tumble the castings. 'Ihis initial blast operation usually dislodges a relatively heavy surge of sand from interior portions of the castings, which is also bypassed to the surge bin 34. When the bulk of .the sand and debris is thus removed from the castings then valve 33 is closed and valve `35 is opened to meter out the contents of bin 34.

Thus Ithe debris and spent iblast media now circulates through the separator 28 and the blast machine 16; the separator functioning to discard from the system the worn 'out shot and .the line debris resulting from the operation. When this process is complete the castings are preferably tumbled for an additional period of time to allow all sand and blast media -to drain from the mill and from the castings before they are unloaded from the mill. It will of course be apparent that the control of the process as outlined above may be performed either manually or autom-atically or semi-automatically as preferred, by any suitable manual or automatic sequencing devices such as a timer which is `adjustable to variable time settings for the various phases of the process. Thus, the optimum duration lof each phase of the process of the invention may be @empirically determined and the control system then set to provide the most eflicient combination of sequential steps for every work load program.

By virtue or this machine arrangement the large initial surge loads of sand and debris which occur when the cores are being dislodged from the castings are temporarily sidetracked to the surge bin, whereby flooding of the separator is avoided. Also, in accord with the present invention the flow of sand and abrasive through the separator and its `associated circulation system may be easily maintained at a ysubstantially constant rate. This avoids the possibility of sand passing through the separator to the blast machine, and also prevents static accumulations of sand at various points in the system such as would otherwise result in statication and periodic dumping (due to vibration) of harmful surges of sand into the system.

Thus, it will be appreciated that the process of the present invention involves the use of only one machine organization, the components of which are substantially y'at all times in constant use and at their peaks of eiciency. It is also a feature of the present invention that the blast media coming to the throwing device 16 is always clean an-d free from debris, thereby rendering the blast operation most eicient and prolonging the life of that equipment. Although only one form of the invention has been shown and described in detail, it will be apparent to those skilled in the art that the invention is not so limited but that various changes may be made therein without departing from the spirit of the invention or the scope of the appended claims.

We claim:

l. The method for sequentially removing cores and 'coarse surface debris from castings or the like and then finish-cleaning the same, which method comprises placing a casting requiring to be cleaned on a support arranged to tumble said casting for shaking out the casting core material land -other relatively loose debris thereby producing a temporary overload of debris in the system, conveying said debris to a separator having a normal debris discharge while by-passing the separator overload to la surge bin, then shot-blasting said casting while being tumbled to remove residual core material and delivering the spent shot and iine debris materials to said separator, and finally surface-cleaning said casting by the sarne shot-blasting machine while recycling back to the separator the accumulation of overload debris collected in said surge bin While redelivering to said blast machine from said separator the reconditioned blast media segregated from the process debris by said separator.

2. A machine system for sequentially knocking out cores and heavy surface debris from castings and then finish-cleaning the same, said machine comprising a casting receiving device adapted to turn the casting, a centrifugal blast machine arranged to bombard the casting as it is turned, a feed Vdevice delivering blast media to said blast machine, a separator receiving debris and spent blast media falling laway from said casting, said separator having a debris discharge and a reusable blast media discharge separate therefrom, said reusable blast media discharge delivering to said feed device, a by-pass conduit conveying overload material from said separator to a temporary storage bin, a dirst valve controlling passage through said by-pass conduit, a second valve controlling discharge from said bin for recycling to said separator, said valves being operable so as to initially divert passage Vof overload debris from said separator to said bin while permitting circulation of material falling away from said casting through sjaid separator, and for subsequently recycling the overload debris and reusable blast media from said bin through said separator and said blast device against said casting.

3. A machine for sequentially knocking out cores and large volume surface debris from castings or the like and then niSh-cleaning the same, said machine comprising a workpiece receiving device adapted to turn the same, a centrifugal blast machine arranged to bombard the workpiece as it is turned, a separator receiving debris and spent blast media falling away from said workpiece, said separator having a debris discharge and a reusable blast media discharge separate therefrom, said reusable blast media discharge delivering to said blast machine, ra by-pass conveying overload material from .said separator to a temporary storage bin, a first valve controlling passage through said by-pass, a second valve controlling discharge from said bin for recycling to said separator, said valves being operable so as to initially `divert passage of overload debris from said separator to said bin while permitting circulation of material falling away from said workpiece through said separator, and for subsequently recycling the overload debris and reusable blast media from said bin through said separator and said blast device against said workpiece.

4. A method ffor sequentially removing cores and coarse debris from workpieces such as castings or the like and then finish-cleaning the same, which method comprises placing :a workpiece requiring to be cleaned on a support arranged to tumble -said workpiece yfor shaking out the relatively loose debris, conveying said debris to a separator while by-passing the separator overload to a surge bin, then shot-blasting said workpiece while being turnbled to remove residual `debris material while delivering the spent shot and ne debnis materials to said separa-tor, and finally surface-cleaning said workpiece by the same shot-blasting machine while recycling back to the separator said overload debris and redelivering to -said blast machine from said separator the reconditioned blast media segregated from the process debris by said separator.

5. A machine for sequentially rough cleaning and then finish-cleaning workpieces, said machine comprising a workpiece receiving device adapted to turn the workpiece, a centrifugal blast machine arranged to bombard the workpiece as it is turned, a feed device delivering blast media to said blast machine, a separator receiving debris and spent blast media falling away from said workpiece, said separator having a debris discharge and a reusable blast media disch-arge separate therefrom, said reusable blast media discharge delivering to said feed device, a bypass conveying overload material \from said separator t0 a temporary storage bin, `a first valve controlling passage 'through said by-pass, a second valve controlling discharge from said bin tfor recycling rto said separator, said valves being operable so as to initially divert passage of overload debris Iaway 'from said separator to said bin while permitting circulation of material Ifalling away from said workpiece through said separator, and for subsequently recycling the overload debris yand reusable blast media from said bin through said separator and said blast device against said workpiece.

References Cited in the iile of this patent UNITED STATES PATENTS 2,104,055 Peik Jan. 4, 1938 2,305,451 Turnbull Dec. 15, 1942 2,424,955 Potter July 29, 1947 2,440,819 Evans May 4, 1948 2,449,745 Jewell Sept. 21, 1948 

2. A MACHINE SYSTEM FOR SEQUENTIALLY KNOCKING OUT CORES AND HEAVY SURFACE DEBRIS FROM CASTINGS AND THEN FINISH-CLEANING THE SAME, SAID MACHINE COMPRISING A CASTING RECEIVING DEVICE ADAPTED TO TURN THE CASTING, A CENTRIFUGAL BLAST MACHINE ARRANGED TO BOMBARD THE CASTING AS IT IS TURNED, A FEED DEVICE DELIVERING BLAST MEDIA TO SAID BLAST MACHINE, A SEPARATOR RECEIVING DEBRIS AND SPENT BLAST MEDIA FALLING AWAY FROM SAID CASTING, SAID SEPARATOR HAVING A DEBRIS DISCHARGE AND A REUSABLE BLAST MEDIA DISCHARGE SEPARATE THEREFROM, SAID REUSABLE BLAST MEDIA DISCHARGE DELIVERING TO SAID FEED DEVICE, A BY-PASS CONDUIT CONVEYING OVERLOAD MATERIAL FROM SAID SEPARATOR TO A TEMPORARY STORAGE BIN, A FIRST VALVE CONTROLLING PASSAGE THROUGH SAID BY-PASS CONDUIT, A SECOND VALVE CONTROLLING DISCHARGE FROM SAID BIN FOR RECYCLING TO SAID SEPARATOR, SAID VALVES BEING OPERABLE SO AS TO INITIALLY DIVERT PASSAGE OF OVERLOAD DEBRIS FROM SAID SEPARATOR TO SAID BIN WHILE 